Full-field wrist pulse signal acquisition and analysis by 3D Digital Image Correlation

•A five dimensional wrist pulse acquisition system based on 3D-DIC is established which provides a novel optical approach for digitalizing pulse diagnosis and massive pulse signal data acquisition for various types of patients.•Full-field displacements maps of wrist fluctuations under different pressure are obtained and analyzed. The analysis results are agreed with the viewpoint in TCM.•Pulse wave velocity under different pressure is calculated out and discussed. PWV estimation under lower pressure is considered to be authentic.

Pulse diagnosis is an essential part in four basic diagnostic methods (inspection, listening, inquiring and palpation) in traditional Chinese medicine, which depends on longtime training and rich experience, so computerized pulse acquisition has been proposed and studied to ensure the objectivity. To imitate the process that doctors using three fingertips with different pressures to feel fluctuations in certain areas containing three acupoints, we established a five dimensional pulse signal acquisition system adopting a non-contacting optical metrology method, 3D digital image correlation, to record the full-field displacements of skin fluctuations under different pressures. The system realizes real-time full-field vibration mode observation with 10 FPS. The maximum sample frequency is 472 Hz for detailed post-processing. After acquisition, the signals are analyzed according to the amplitude, pressure, and pulse wave velocity. The proposed system provides a novel optical approach for digitalizing pulse diagnosis and massive pulse signal data acquisition for various types of patients.